Interlisp (also seen with a variety of capitalizations) is a programming environment built around a version of the Lisp programming language. Interlisp development began in 1967 at Bolt, Beranek and Newman in Cambridge, Massachusetts as BBN LISP, which ran on PDP-10 machines running the TENEX operating system. When Danny Bobrow, Warren Teitelman and Ronald Kaplan moved from BBN to Xerox PARC, it was renamed Interlisp. Interlisp became a popular Lisp development tool for AI researchers at Stanford University and elsewhere in the DARPA community. Interlisp was notable for the integration of interactive development tools into the environment, such as a debugger, an automatic correction tool for simple errors (DWIM – "do what I mean"), and analysis tools.